There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{({z}^{2} + 3)}{(x + z)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{z^{2}}{(x + z)} + \frac{3}{(x + z)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{z^{2}}{(x + z)} + \frac{3}{(x + z)}\right)}{dx}\\=&(\frac{-(1 + 0)}{(x + z)^{2}})z^{2} + 0 + 3(\frac{-(1 + 0)}{(x + z)^{2}})\\=&\frac{-z^{2}}{(x + z)^{2}} - \frac{3}{(x + z)^{2}}\\ \end{split}\end{equation} \]

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